渭河盆地GPS应变背景特征及高陵地震发震原因探讨  

Discussion of GPS Strain Background Characteristics of Weihe Basin and the Underline Cause of Gaoling Earthquake

作　　者：丁晓光[1,2] 韩晓飞[1] 张永奇[1] 苏利娜[1] 张艺[1] 

机构地区：[1]陕西省地震局,西安710068 [2]中国地震局地质研究所,北京100029

出　　处：《震灾防御技术》2014年第B10期665-671,共7页Technology for Earthquake Disaster Prevention

基　　金：国家"十二五"科技支撑项目(2012BAK19B02);中国地震局地震行业专项(201208009-13);陕西省"十二五"关中地区大震危险性评价项目共同资助

摘　　要：本文基于陕西2001—2010年流动GPS网观测数据,利用GAMIT/GLOBK软件对该数据进行处理,获得了渭河盆地高精度的水平运动速度场。利用最小二乘配置法得到区域应变背景特征参数,进而对高陵4.4级地震发震的可能原因进行分析。通过对主应变、剪切应变、面应变等分析研究,得到如下结论:高陵地震的发震区域易于积累剪切应变,并且容易受到应力调整的影响。汶川大震后引起周边应力重新分配调整,可能是高陵地震发生的关键要素。GPS应变场可以反映区域断层运动性质,与地质构造活动有着较好的一致性。With the data of GPS mobile observation network in Shaanxi province during 2001--2010, the high-precision horizontal velocity field of Weihe basin processed by the software of GAMIT/GLOBK was obtained. The regional strain background characteristic parameters were calculated according to the velocity and strain theory by least squares collocation method, which were used in the analysis of underline cause of Gaoling M4.4 earthquake According to principal strain, shear strain and plane strain, we could reach the conclusion that the seismogenic region could accumulate the shear strain easily, and be sensitive to the influence of stress changes. After the Wenchuan earthquake, the stress of epicenter nearby had been newly distribution and adjustment, that might be the key factor of the occurrence of Gaoling earthquake. On the other hand, the GPS strain field could reflect the characters of the regional fault movement, which had a good consistency with the tectonic activity.

关 键 词：GPS 应变特征 高陵地震 渭河盆地 

分 类 号：P315.1[天文地球—地震学] P315.727[天文地球—固体地球物理学]